Current modulation circuits are used in a number of applications. The Peripheral Sensor Interface (PSTS) is an interface used, for example, in automotive sensor applications wherein an electronic control unit (ECU) and sensor are coupled by a two-wire interface supporting both power supply and data transmission. The ECU provides a regulated voltage to the sensor, and the sensor transmits data to the ECU on the supply line using current modulation. The current modulation is detected by the ECU and decoded to recover the original digital data stream generated at the sensor.
Specifications governing configuration and operation of the interface must be followed by the current modulator in the sensor when transmitting data to the ECU. There is a need in the art for a current modulator circuit that operates in accordance with specifications and without introducing distortion.